6 October 2017 - - Kyowa Hakko Kirin Co., Ltd , the Japan and Korea sublicensee of US-based biopharmaceutical company Syndax Pharmaceuticals, Inc. (NASDAQ: SNDX), has dosed the first patient in a randomized, double-blind, placebo-controlled, pivotal Phase 2 trial of entinostat, Syndax's oral Class-I histone deacetylase inhibitor, in combination with exemestane versus exemestane plus placebo in Japanese patients with advanced or recurrent hormone receptor-positive, human epidermal growth factor receptor two-negative (HER2-) breast cancer, the company said. 
Enrollment of the first patient in this trial triggers a USD5 m milestone payment to Syndax from Kyowa Hakko Kirin.
The Phase 2 trial is expected to enroll approximately 124 patients in Japan. The primary endpoint of the trial will be progression free survival, with secondary endpoints including overall survival, overall response rate, and safety.
Syndax is developing an innovative pipeline of cancer therapies. Its lead product candidate, entinostat, which was granted Breakthrough Therapy designation by the FDA following positive results from its Phase 2b clinical trial, ENCORE 301, is currently being evaluated in a Phase 3 clinical trial in combination with exemestane for advanced hormone receptor positive, human epidermal growth factor receptor 2 negative breast cancer.
Given its potential ability to block the function of immune suppressive cells in the tumor microenvironment, entinostat is also being evaluated in combination with approved PD-1 antagonists.
Ongoing Phase 1b/2 clinical trials combine entinostat with Keytruda from Merck and Co., Inc. for non-small cell lung cancer, melanoma and colorectal cancer; with Tecentriq from Genentech, Inc. for triple negative breast cancer; and with Bavencio from Pfizer Inc. and Merck KGaA, Darmstadt, Germany, for ovarian cancer.
The company's second product candidate, SNDX-6352, is a monoclonal antibody that blocks the colony stimulating factor 1 (CSF-1) receptor and may also block the function of immune suppressive cells in the tumor microenvironment. SNDX-6352 is being evaluated in Phase 1 clinical trials and is expected to be developed to treat a variety of cancers.
Kyowa Hakko Kirin is a research-based life sciences company, with special strengths in biotechnologies. In the core therapeutic areas of oncology, nephrology and immunology/allergy, Kyowa Hakko Kirin leverages leading-edge biotechnologies centered on antibody technologies, to continually discover innovative new drugs and to develop and market those drugs world-wide.
Syndax Pharmaceuticals is a clinical stage biopharmaceutical company that focuses on the development and commercialization of therapies for various cancer indications.